Telephone-exchange system.



J. L. MCQUARRIE.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED NOV. 20.1917.

Patented July 9, 1918.

UNITED STATES PATENT OFFICE.

JAMES L. MGQUARRIE, 0F MONTCLAIR, NEW JERSEY, ASSIGNOR TO WESTERNELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A. CORPORATION OFNEW YORK.

TELEPHONE-EXCHAN GE SYSTEM.

Specification of Letters Patent.

Patented July 9, 1918.

Application filed November 20, 1917. Serial No. 202,934.

To all whom it may concern:

Be it known that I, JAMns L. MCQUARRIE, a citizen of the United States,residing at Montclair, in the county of Essex and State of New Jersey,have invented certain new and useful Improvements in Telephone- ExchangeSystems, of which the following is a full, clear, concise, and eXactdescription.

This invention relates to automatic switches, and more particularly toautomatic switches of the type used in telephone exchange systems.

This invention is an improvement upon applicants copending application,Serial No. 158,567, filed March 30, 1917.

It is the object of this invention to provide a switch which shall bemechanically simple, and also compact and low in cost of construction.

A feature of the present invention is the use of a contact bank of thepanel type in connection with a switch of the well-known up and aroundstructure. The contact banks are essentially Similar to those used anddescribed in the above mentioned application, excepting that each shelfof contacts is provided with multiple contacts on its lower surface aswell as on its upper surface. It is obvious that by this arrangement,the number of shelves to be used will be halved.

A feature of this invention is the use of a brush set arranged tocontact with the terminals on the lower surface of said contact banksupon movement in a rotary direction after the completion of an oddnumber of steps in a vertical direction; and arranged to be moved in arotary motion over the upper surface of the contact banks uponcompletion of an even number of vertical steps.

, It is thought that the invention will be best understood from thefollowing detailed description, reference being had to the accompanyingdrawings.

In the drawings, Figure 1 shows a perspective view of the essentialoperating elements of the switch, together with a suitable circuitarrangement for controlling the same;

Fig. 2 shows aplan view of a contact bank shelf with a brush carriage inits normal relation tosaid bank;

Fig. 3 is a plan view showing in what relationto one another a pluralityof switches are mounted so as to be accessible to the same contact bank;and

Fig. 4 is a detailed view of a double brush set constructed inaccordancewith the principles of this invention.

Referring now to Fig.1, it will be seen that there are provided aplurality of contact banks such as 10, 10 and 10". The construction ofthese contact banks will be better understood by reference to Fig. 2. InFig. 2 the unit contact bank is indicated generally at 10 and is shownto be made up of a number of strips of conducting material, as indicatedat 11, 12, 13, 14, 15 and 16, all suitably insulated from one another,in the manner usual in the panel type of Contact bank construction.These strips are arranged to run longitudinally the entire length of theshelf 10 and are provided at each switch with bent-over contact portionsas 17, 18 and 19 to provide terminals for engagement with the brush setcarried by arm 20. The location of the bent-over contact portions of thevarious strips is so arranged that the contacts may be engagedsuccessively by the brush carried by arm 20, upon rotation of said arm.At 21 is indicated an arm of the switch adjacent to that controlling thearm 20. The relation of the switches and contacts may be betterunderstood by inspection of Fig. 3, which shows a number of switches inrelation to a contact bank shelf.

As described in the previously mentioned application, these shelves areto be arranged one above the other, so that when the brush carriage iselevated to a desired level, the brush may then be rotated transverselyof the contacts to select the desired set of contacts. Therefore in theprevious arrange ment it was necessary to provide as many layers orshelves'of multiple panel strips, each accessible to a plurality ofswitches, as there were groups of contacts. If it was desired that theswitch should have access to ten groups of terminals, ten shelves ofcontacts were required in the previous arrangement. In the presentarrangement, however, referring to the bank 10 in Fig. 1, it

.will be seen thateach shelf is provided with vfive shelves will beneeded to provide access to ten groups. As shown in Fig. 1, thecontacts, of the first group and second group are insulated from oneanother in a suitable manner as indicated by the insulating strip 22.

The contact banks are so arranged that upon the completion of the firstvertical step by shaft 23, the brushes 24, 25 and 26 will be in aposition to engage the contacts on the lower side of shelf 10. Upon thecompletion of the second group step, the brushes 27, 28, 29 will be in aposition to engage the contacts on the upper side of shelf 10 On thecompletion of the third group step, the brushes %4,- 25 and 26 will bein a position to engage the contacts on the lower side of shelf 10'.

The mechanism for operating the brush carriage may be .that of anywell-known type of up and around switch and any one of a number ofwell-known circuit arrangements may be used therewith. The switch isequally adapted for use as a selector or connector.

Refer-ring now to Fig. 1, a brief description of the operation of thedevice as a seleotor switch will be given. Assuming that the subscriberwhose-substation, is indicated at 30, desiresa connection, he willremove his receiver from the switchhook, whereupon his line will beextended in any desired manner to the selector whose circuits are shownin Fig. 1. In the present case, it will be assumed that the means forextending his line to the selector is a line finder, whose brushes areindicated at 81, 32 and 33.

As soon as the line finder has operated, a circuit is completed fromgrounded battery, right-hand windingof line relay 34, side-switch wiper35 in its first position, finder brush 31, contact 36, through the loopof the calling subscribers. line, contact 37, finder brush 32',side-switch wiper 38, in its first position, left-hand winding of relay34 to ground. Relay 34 is energized and attracts its armature,completing a circuit from grounded battery, winding of slow releaserelay 39, armature and front contact of relay 3'4 to ground.

The subscriber now operates his sender, indicated at 40, to cause aseries of inter- ;ruptions in the line circuit. Upon the firstdeenergmatron of line relay 34, a circuit is completed from groundedbattery, winding of slow release. magnet 41, armature and from contactof relay 39, armatureand back contact of relay 34 to ground; Relay 41 isenergized and completes a, circuit from grounded battery, windingofescape magnet 42, side-switch wiper 43, in itsfirst position, armatureand frontcontact "of relay 41. to gr0i1nd; parallel with thecirctiit ofrelay 41, a circuiti s completed from grounded battery,'winding ofvertical 'st'eppin magnet 44,secondary ofi -normal' contact 4 armatureand frontcontact ctr-clay: 39; armature and back Contact of relay 34 toground. Magnet 44 is energized and advances the brush shaft 23 one stepin a vertical. direction. Magnet 44 is, energized in response to eachinterruption of the line circuit, but relays. 39 and 41 being slow torelease, remain energized during the sending of the impulses Uponcompletion of the firstseries of impulses, at which time the shaft 28has been elevated to the desired contact level, line relay 34 remainsenergizedfor a relatively long period er time, causing thedeenergization of relay '41. gization of relay 41 causes in turn thedeenergization of escape magnet 42,;which releases and allows theside-switch wipers to be advanced, in, their second position.

In the second position of the side switch a circuit is completed fromgrounded battery, contact springs 45, winding of rotary stepping magnet46-,- side-switeh wiper ($0,- in its second position, armature and frontcontact of relay 34 to ground. Magnet 46 attracts its armature toadvance the brush shaft 23 one step in a rotary direction, thus openingthe contact 47" to prevent further actuation of the vertical steppingmagnet 44. Magnet 46, upon attraction of its armature, interrupts itsown circuit at springs 45 and deene'rgizes. Magnet 46 continues tointerrupt its own circuit and advances the brush set over the selectedcontact bank until an idle trunkis found. If it is assumed that the idlecondition of trunks is indicated by the presence of ground potential onthe test terminals of Said trunks, it will be observed 7 that the escapemagnet 42' is energized as soon as the brush set is positioned on theterminals of an idle trunk. This circuit.- for escape magnet 42 extendsfrom grounded battery, winding otescape magnet- 42, side switch wiper43, in its secondpositiomconductor'48, test brush 26 or 29, according towhether an even or odd numberof steps has been taken, to ground by wayof the test terminal of the idle trunk; The energiZation of escapemagnet 42 advances theside-switch wipers into their third position, thusopening the circuit of magnet 46; and bringing the brush set to restupon the terminals of an idle trunk in the selected group.

Upon completion of conversation ground will be applied to conductor 48from the connector in the wen-known manner, whereupon a circuit will becompleted iron grounded battery, winding of release ma-gnet5ft),-priinary ofi normalcontaetsol, side- 7 switch wiper 52,5111 itsthird position, eonductor-48 to ground. Magnethtl is energized andoperates the double holding dog -to withdraw pawls 53 and 5415mmengagement with thevertical and rotary ijatcliets respectively, to allowthe switeh'tobe released; f It is to be observed that magnet 50* upon.en-

ergizer-ion completes a ieeieng circuit for itself by way of primaryoff-normal contact 51, conductor 55, contacts 56 to ground. Magnet 50therefore remains energized until the switch has been completelyrestored, at which time the circuit of magnet 50 will be broken by theopening of off-normal contacts 51.

lVhat is claimed is:

1. In an automatic switching device, a multiple terminal bank comprisinga plurality of sections arranged in superimposed tiers, each tier beingprovided with an upper and lower contact bearing surface, each of saidsurfaces comprising a separate group of multiple terminal strips,switching mech anisms in operative relation to said terminal bank, andmeans to operate a switching mechanism to select a desired group ofcontacts and to select a desired contact in a selected group.

2. In an automatic switching device, a multiple terminal bank comprisinga plurality of sections arranged in superimposed tiers, each tier beingprovided with an upper and lower contact bearing surface, each of saidsurfaces comprising a separate group of multiple terminal strips, aplurality of movable brush carriages, a brush set carried by each ofsaid brush carriages, means to advance a brush carriage to select adesired group, and means to advance said brush carriage transversely ofa selected group to position its associated brush set on a desiredterminal set in the selected group.

3. In an automatic switching device, a plu rality of switchingmechanisms, movable contacts controlled thereby, a multiple terminalbank comprising a plurality of sections arranged in superimposed tiers,each tier being provided with an upper and a lower contact bearingsurface, each of said surfaces comprising a plurality of terminal stripssuitably insulated from one another, contact portions on said stripsprojecting at desired intervals and in proper relation to one another,said contact portions being suitably oflset for engagement with movablecontacts of said switching mechanism, means to operate one of saidswitching mechanisms to advance its movable contacts carried therebyinto operative relation with one of said contact bearing surfaces toaccomplish group selection, and means to advance said movable contactstransversely of said selected surface to select a desired terminal setin the selected group.

4. In an automatic switching device, a multiple terminal bank comprisinga plurality of sections arranged in superimposed tiers, each tier beingprovided with an upper and lower contact bearing surface, each of saidsurfaces comprising a separate group of multiple terminal strips,switching mechanisms in operative relation with said terminal bank,means to cause vertical motion of a switching mechanism to select adesired group of contacts, and means to cause rotary movement of aswitching mechanism to select a desired contact in a selected group.

5. In an automatic switching device, a multiple contact bank comprisinga plurality of unit layers placed in superimposed relation, a pluralityof movable brush carriages, brushes-carried thereby, means to advance abrush carriage into position to select a desired group, and means toadvance said brush carriage transversely of a selected group to enablethe associated brushes to engage contacts in said selected group, andmeans to advance said brushes over contacts on the lower surface of aselected layer or over contacts on the upper surface of a selected layerin accordance with whether the number of group steps taken by saidcarriage is odd or even.

6. In an automatic switching device, a multiple contact bank comprisinga plurality of superimposed unit layers, each of said layers beingprovided with contact sets on its upper surface and on its lowersurface, vertically and rotatably movable shafts in operative relationto said contact bank, a brush carried by each of said shafts, means toselectively move a brush during vertical movement of said shaft toselect a desired group of contacts, and means to move said brush duringrotary movement of said shaft transversely into engagement with adesired contact in the selected group.

In witness whereof I hereunto subscribe my7name this 16th day ofNovember, A. D. 191

JAMES L. MOQUARRIE.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, I). 0.

